In fabrication of a semiconductor device, a photolithography process is used to form a predetermined resist pattern on a substrate such as a semiconductor wafer (“wafer”). In the photolithography process, for example, a plurality of processes, such as a coating process, an exposure process, a heating process, and a developing process, are sequentially performed to form the resist pattern. In the coating process, a resist liquid is coated on the wafer to form a resist film. In the exposure process, the resist film is exposed in a predetermined pattern. In the heating process (post-exposure baking), a chemical reaction within the exposed resist film is facilitated after the exposure process. In the developing process, the exposed resist film is developed. A series of processes as described above are performed by a coating/developing system mounted with various process devices such as a coating device, a heating device, and a developing device, and a wafer carrying device, etc. Also, in such a coating/developing system, for example, a plurality of wafers to be processed with the same recipe are sequentially carried and processed.
In such a coating/developing system, a series of processes described above have to be performed while maintaining a predetermined level. For this reason, after the series of processes are performed, the distribution of estimation parameters, such as critical dimensions (CDs) of a resist pattern, has to be obtained within a wafer plane. In the coating/developing system, this distribution is obtained for example by processing a test wafer, and measuring the estimation parameters at a plurality of estimation points within a plane of the test wafer by a measuring device mounted in the system before processing of product wafers. See, for example, Japanese Laid-Open Patent Publication No. 2008-84886.
For example, in a heating device included in a coating/developing system, a heating plate is divided into a plurality of divisions in order to reduce the temperature fluctuation within a plane of a wafer. Then, by changing the setting temperature of each of the plurality of divisions, a heating process for facilitating a chemical reaction within an exposed resist film is controlled in such a manner that the heating process can be uniformly performed within a wafer plane. In the example described in Japanese Laid-Open Patent Publication No. 2008-84886, a control process is performed in such a manner that the CDs of a resist pattern are measured at a plurality of measurement points within a wafer plane, the distribution of the CDs within the wafer plane is obtained, and the setting temperature of a heating plate is corrected.